Artificial limb



Sept. 9 1924.

A. PECORELLA ET AL ARTIFICIAL LIMB 2 Sheets-Sheet 1 Original Filed Jan.

Sept. 9, 1924.

A. PECORELLA ET AL ARTIFICIAL LIMB 2 Sheets-Sheet 2 Original Filed Jan.24 1919 INVENTOIRS ATTORNEYS Patented Sept. 9, 1924.

UNITED STATES PATENT.OFFICE.

ALBERTO PECORELLA AND PAT BICOLO, or Borruo, AND: manna-Ion H.

Area, or A'IHOL sra Nos'N w roan, ass'reivons, sarcasm: .Ass'IeNm'rs,'ro' LIVINGSTON ARTIFICIAL LIMB' COMPANY, or NEW YORK, 111;, ACORPORATION OF DELAWARE.

ARTIFICIAL v1411MB.

Substitute for abandoned application seri al 1T0. 272,808ffl1ed Januarylarch 17, .1924.

To all whom it may concern."

Be i known that we, AL ERTOZPE ORELLA,

a citizen of the United States, and resident of Buffalo, in the countyof Erie and'State" of New] York, VINCENT Parnroonmauslib'ff ject of .theKing of Italy, and residing at" Buffalo, in the county of Erie'and Stateof New York, and FREDERICK H. APEL, a citi- Springs, in the county ofErie and State of New York, have invented new and useful Improvements inArtificial Limbs, of which the following is a specification.

' This invention relates to an artificial limb action of thecorresponding part'ofa living person very closely and with ease andcomfort, so that the user will be ableto obtain nearly as much use ofthe same as from a real hand.

This application is "a substitute for abandoned application No. 272,808,filed January 24, 1919. In the accompanying drawings:

of an artificial limb embodying our im rovements, the section beingtaken perpen icular to the plane of the palm of the hand and on line1-1, Fig. 2. Figure 2 is an elevation, partly in section. of theartificial limb viewed from the palm-side of the hand. Figure 3 is afragmentary longitudinal sec- 4 tion showing one of the fingers of theartificial limb in its folded or closed position.

actuating one of the fingers, the section being taken on line 44, Fig.2. Figures 5 and 6 are cross sections taken onthe correspond:

serial. in. 699,950.

Similarcharacters of refere in i I ally connected'at zen of theUnitedStates, residingv at Athol Figure 1 is a vertical longitudinalsection Figure 4 is a fragmentary section, on an enlarged scale, of partof the means forv 24,: 1919. This application med corresponding partsthroughout the several 1; Ourimprovexnents are. adapted to be associatedwith anarm-section '1 which may be attached to .thej-stumpof the realarm in any suitable manner, a forearm 3 which is pivotits rear end withthe front end of the arm by means of a transverse in 2, a wrist 4 whichis pivotally connec at its rear end with the front end of the forearm soasto be capable of turning relatively thereto about a longitudinal axis,a palm 5 which is pivotally connected at its rear. end with'the frontend of the wrist by means of a transverse pin 6 so as to be capable oftuming laterally relatively to the palm, a plurality of digits, thefingers of which consist each of a first section 7 pivotally connectedwith the palm byapin 8, a second section 9 pivotally connected with thefirst section by means of-a'pin 10, and athird section 11 pivotallyconnected with the second section by means of a pin 12, and a thumbcomprisinga first section 13 pivoted'on the palm by a pin 14 and asecond section 15 pivoted on thefirst section by means of a pin 16. Allof these several members. are preferably constructed of hollow'ortubular form in any suitable and approved manner so that the mechanismfor operating the same may be located in the interior thereof.

Inasmuch as the means for actuating the several fingers for folding orclosing and unfolding or opening the same are alike, the followingdescription applying to. one of them will apply to all of the severalfingers.

'24 represents a. worm-gear segment arranged within the inner part ofthe first section of each finger and connected therewith concentricallyrelative to the pivotal connection between thisfinger section and thepalm. With this worm-segment engages a worm 25 the axis of which isarranged erpendicular to the plane of the palm. U pon turning thiswormin one direction or the other, the first finger-section will be turnedeither into its open or closed position. Within the inner part of eachfinger-section and the adjacent part of the palm is arranged a firstlever 17 which is pivoted between itsrear and front arms by means of apin 18 on the adjacent part of this finger section on one side of theaxis of the pivotal connection 8 between this finger section and thepalm. The inner or rear arm of thls first lever is free to slidelengthwise but 1ncapable of turning, this being accomplished by passingthis rear arm through an opemng formed in a cross bar 19 which ismounted rigidly on the inner side of the palm. 20 represents a secondlever which is arranged partly in the first and second finger-sectionsand is pivoted between its arms by means of a transverse pin 21 on thesecond fingersection on one side of the pivotal connection 10 betweenthe first and second finger-sections. The inner arm of this second leveris pivoted to the front arm of the first lever 17 and the front or outerarm of this second lever is connected with the inner end of a link 22which latter is arranged within the second and first finger sections andhas its front end connected by a pivot 23 with the third finger sectionon one side of the pivotal connection 12 between the second and thirdfinger sections.

In the position of the parts shown in Figs. 1 and 2, the several fingersare all unfolded to their maximum extent in which position the first andsecond levers 17, 20 and the link 22 are arranged substantially in line,the pivot of the first lever is arranged out wardly from the pivot 8which connects the palm and the first section and the pivots 21, 23 ofthe second lever and the link are arranged a considerable distanceoutwardly from the corresponding pivots 10, 12, which connect the secondfinger section with the first and third sections. Upon turning the worm25 in the direction for folding or closing the first finger-section, thefirst lever 17 will slide through the cross bar 19 without, however,rocking on its fulcrum 18 to any appreciable extent, which relative movement of the first finger section and the first lever will cause aninward pull upon the second lever 20 which is connected with the secondfinger section, so that this second lever at this time operates as alink and causes the second finger-section to be shifted into its foldedor closed position. as indicated in Fig. 3. Inasmuch as the relativeposition of the second lever and the second finger section is changed bythis last-men tioned operation, a pull is produced by the front arm ofthe second lever 20-upon the third finger section through the medium ofthe link 22, so that this thirdfinger section is shifted from itsunfolded position shown in Fig. 1, to its folded or closed positionindicated in Fig. 3. A reversal of the turning motion of the firstfinger-section by operation of the worm-gear and worm, will cause thesecond and third finger-sections to be unfolded from the osition, shownin Fig. 3 to that shown in. ig. 1, through the action of the first andsecond levers 17, 20 and the link 22. v

A construction similar to that for operating each of the fingers isemployed for operating the first and second sections of the thumb. Thisthumb-operating movement comprises a worm-gear segment 50 secured to theinner thumb-section 13 concentric with the pivot thereof. a worm 51arranged at right angles to the worms of the fingeroperating mechanismand meshing with the thumb gear-segment. The outer or secondthumb-section is yieldingly held in its unfolded position by a spring 49which preferably has a central coil surrounding the pivot 16 while itsopposite ends are connected respectively with the inner and outerthumbsections, as shown in Fig. 2. Upon turning the first thumb-sectioninwardly by means of the worm 51 and wormgear 50, the outerthumb-section moves bodily with the inner thumb-section until the outerthumbsection engages the adjacent first finger at which time thethumb-spring 49 yields and permits the outer thumb-section tr standstill independently of the inner thumbsection and thereby enable thehand to close in imitation of a fist without breaking any of the parts.A reversal in the movement of the thumb-worm and gear-segment causes thethumb-sections to be again unfolded.

An actuating mechanism is provided for the several diglts whereby thesame ma be simultaneously closed and opened but which is so organizedthat if any one of these digits encounters any obstruction which resistsits movement in one direction or the other, such digit may remain atrest independently of the remaining digits and thereby enable the handwhen the same is closed to grasp irregularly-shaped objects in imitationof the operation of the human hand. This is accomplished in the presentcase by associating with each digit, means having parts which cooperatefrictionally with each other so that the main actuating mechanism forthe several digits may slip with reference to one or more of the digitswithout inter fering with the closing or opening operation of theremaining digits whose freedom of motion is not obstructed. Thepreferred form of this friction device employed with each of thefingers, as shown 1n the drawings, is constructed as follows:

26 represents a shaft upon which .the finger-worm 25 is mounted andwhich is seated at its opposite .ends in bearings formed in the top. ofthe palm 5 and in the adjacent art of the cross bar 19. At its inner enthe worm 25 engages with a shoulder or collar 27 on the shaft 26 and onits outer end the same is provided with a conical friction surface 28which is enlgaged by a correspondingly-shaped conical friction surface30 formed on a driving .head 29 mounted on the adjacent part of :theworm shaft 26. This driving-head is yieldinglypressed with itsfriction-face ;a'ga'in st that of the adjacent worm by means ,of aspring 31 surrounding the outer part of;

-theshaft 26 and engaging its inner endwith threaded outer "in Fig. 4.

" the-driving-head while its ,outer end bears against a screw net 32engaging with the 80 represents a sprocket wheel or rim formed on theouter part of each of the driving-heads. Between adjacent sprocketwheels of the several finger worm-gears are .arranged intermediate oridle sprocket 1 wheels 33 which are pivoted on the adjacent part of thepalm. Within the central part of the palm is arranged a main or mastersprocket-wheel 34 which is mounted on a spindle 36 turning on the palmin bearings which are arranged thereon at right angles to the plane ofthe palm. A sprocket chain-belt 35 passes around the main sprocket wheel34, the driven sprocket wheels 80 of the several driving heads andtheidle sprocket wheels 33, so that upon turning the main sprocket wheel inone direction or the other, all of the driving heads ...will besimultaneously turned for opening or closing the fingers. If, at thistime the fingers meet with no obstruction, the frictional connectionbetween the driving heads and the adjacent worm wheels will cause theseveral fingers to open and close in I unison, but if the movement ofany one or more of the fingers is interfered with, the respective"finger will lag behind due to the slipping action of the frictionalcontact between the corresponding driving head and yvorm while theremaining fingers which meet with no obstruction will operate nor-.mally during their opening and closing movement. If a finger has beenpermitted to close only partly by reason of meeting an obstruction inadvance of the remaining fingers, then this finger during the reversalin the movement of the driving sprocket wheel 34 and associated partswill reach its fully open position in advance of the remaining fingersand when the latter are also moved into their fully open position thedriving head of the respective finger which has already reached its openposition will simply slip in frictional contact with the respective wormwheel until the several parts have been all brought back into theiruniformly open position.

In order to thus insure the full opening and closing action of theseveral fingers, the rotary movement of the rimary or driving sprocketwheel 34 is so etermined that the finger-operating mechanism willreceive motion from this main sprocket wheel in expara Jf the shaft 26,as shown cess of that required for fully opening and closing the, same.This motion of the driving sprocket wheel 34 may be derived from anysuitable source and transmitted thereto by any suitable means. Forinstance, as shown in the drawings, this may be eflfected by a closingline 38 and an opening line 37 arranged in the wrist, forearm and armand connected at their rear. ends in any: suitable manner with somemovable IfltTlbel' of body, so that these two lines'may be alter natelydrawn in opposite directions, the inner or front ends of these linesbeing connected with the driving gear wheel on di-. ametrically oppositesides thereof, as shown in Fig. 2, so that upon pulling on the closingline the driving wheel will be turned in the direction for closing thefingers and when pulling upon theopening line the several fingers willbe opened.

Owing to the location of the thumb on the palm at an angle to theseveral fingers, a slight modification'in the form of the mechanism fortransmitting motion from the chain belt 35 tothe thumb-worm is'employed, which mechanism in its preferred form isshown in Figs. :2, 7and 8 and constructed as follows:

52 represents a worm shaft arranged within the palm parallel with theplane thereof and journaled in bearings therein. The thumb worm 51 isconnected frictionally with this shaft so that when the thumb is free toturn this worm will rotate with its shaft but if the thumb meets with anobstruction ths shaft will be able to turn independently of thethumb-worm. For this purpose the outer end of the thumb-worm engageswith a shoulder or collar 53 on a thumb-shaft 52 and the inner end ofthis worm is provided with a conical friction face 54 which is engagedby a correspondingly-shaped conical .friction face 55 on a driving head56 which is splined on this shaft andpressed yieldingly against therespective worm by means of a spring 57 surrounding this shaft andengaging its outer end against this driving head while its inner endengages with a screw nut 58 arranged on this shaft, as best shown inFig. 8. A rotary motion is imparted to the thumb-operating shaft 52 bymeans of an intermediate shaft 59 journaled on the palm and providedwith a driven sprocket wheel 60 which is en aged by the chain belt 35,and also provided with a beveled gear-Wheel 61 meshing witha beveledgear wheel v62 on the thumb-operating shaft 52. In this manner thethumb-sections are folded and unfolded in un son with thefinger-sections in substantially the same manner, so that thethumb-sections either move with the finger-sections or are free to staybehind in the event that they strike an obstruction which resists themovement of these thumb-sections in either direction.

The pivotal connection between the palm and the wrist is intended topermit turning the palm laterally with reference to the wrist inimitation of the action of the human hand in this respect. The meanswhereby this is accomplished are preferably constructed as follows:

40 represents a worm arranged within the wrist and meshing with a wormgear segment 39 mounted on the inner end of the palm concentric with thepivoted connection between the same and the wrist. This palm operatingworm is providedwith a driven sprocket wheel 41 which receives a chainor sprocket belt 42 oneiend of which is attached to the digit openingline 37 and the other to the digit closing line 38, as shown in Figs. 1and 2. By this means a rearward pull upon the closing line will causethe palm operating worm to be turned in the direction for tipping thepalm laterally inward with reference to the wrist at the same time thatthe digits are closed relatively to the palm, and a rearward pull uponthe opening line will cause the palm to be swung outwardly relatively tothe wrist at the same time that the digits are again moved into theiropen or unfolded position.

When pressing the palm in either direction against an object it isdesirable to per mit the same to yield to some extent in order tosimulate the action of the human palm in this respect when engaging anunyielding object. This is possible in the present case by mounting thepalm-operating worm and sprocket wheel upon a spindle 81 which ismounted within the palm, so that this worm and sprocket wheel arecapable of longitudinal movement on the spindle and providing twosprings43, 44 which are mounted on this spindle and engage their inner endswith opposite ends of this worm and sprocket wheel while their outerends engage with the adjacent bearings of this spindle, as shown in Fig.9, orother suitable shoulders or abutments which may be provided withinthe palm for this purpose. The tensions of the springs 43, 44 are sodetermined that they normally operate to hold the palm-operating wormand sprocket wheel in their central position, but if a lateral pressureis exerted upon the palm or the fingers mounted thereon independently ofthat which is exerted by the palm-operating worm, then the lattertogether with its sprocket wheel will be moved lengthwise on the spindle81 on one direction or the other and flex one or the other of thesprings 43. 44, which yieldingly resist this deflection of the palm orfingers. When such deflection ceases the righting springs 43, 44 againreturn the palm-operating worm into its central or neutral positiontogether with the parts mounted thereon.

Although the pivotal connection between the wrist and the forearm may beeffected by various means that which is shown in I the drawings issuitable and preferred and as there shown the same comprises two platesor disks 63, 64, which are secured to the opposing ends of the forearmand wrist, respectively, a ball bearing 65 interposed between the outermarginal parts of these plates, a pivot bolt having a cylindrical rearpart 66 which engages with a cylindrical opening in the forearm plate, asquare front part 67 which engages with a square opening in the wristplate, a screw nut 68 applied to the screw threaded front end of thebolt and engaging with the front side of the Wrist plate, and a head 69arranged at the rear end of the bolt shank and engaging by means of aninterposed ball bearing 70 with the rear side of the forearm plate, asshown in Figs. 1, 2, 5 and 6. By means of this pivotal connectionbetween the wrist and forearm, these two members are free to turnrelatively to each other about a longitudinal axis without any bindingor cramping of the parts.

The rotary motion of the wrist withreference to the forearm ispreferably derived by utilizing the relative turning motion of theforearm and arm. This is preferably accomplished by means of aworm-wheel 71 arranged on the head 69 of the pivot or coupling bolt, atransverse shaft 73 arranged within the forearm and journaled insuitable bearings thereon, a worm 72 mounted on this shaft and meshingwith the worm wheel 71, a gear pinion 82 mounted on the shaft 73, a gearrack 74 meshing with the gear pinion 82 and guided in the forearm plate62 and in a bracket 78 on the forearm, and a link 76 pivoted at itsfront end on the rack 74 and pivotally connected at its rear end withthe arm 1 on one side of the pivot 2 between this arm and the forearm,as shown in'Figs. 1 and 2. By this means a turning motion of the forearmrelatively to the arm causes the gear rack to be shifted lengthwise ofthe forearm and turn the gear pinion 82 which latter causes the worm 72to rotate the worm wheel 71 together with the wrist and parts mounted onthe latter. 7 In order to avoid interference between the gear rack andthe wrist plate 64 the latter is provided with a segmental slot 77 whichreceives the front part of the rack, as shown in Fig. 5, and for thesame reason the forearm plate 63 is provided with a segmental slot 79which receives the opening and closing lines 38, 37, as shown in Fig. 5.

It will be noted that the several devices embodied in this invention arecomparatively simple in construction considering the the several movablemembers so that they simulate the corresponding human parts with greatnicety and permit of using the hand in practically the same way as thenatural hand.

We claim as our invention: 1. An artificial limb, comprising a palm, adigit having a first section pivoted on said alm and a second sectionpivoted on said i irst section, and means for operating said firstsection comprising a lever pivoted on said first finger section on oneside of the ivotal connection between said palm and rst section, a guideon the palm for the rear arm of said lever, and an operatin memberconnected at its rear end with the out arm of said lever andpivotallymonnected at its front part with said second section on oneside of the pivotal connection between the first and'second sections.

2. An artificial limb, comprising a palm, a' digit having a firstsection pivoted on the palm, a second section pivoted on the firstsection and a third section pivoted on the second section, and means foroperating the second and third sections comprising a first lever pivotedon the first section on one side of the pivotal connection between thelatter and the palm, a guide on the palm for the rear arm of said firstlever, a second lever pivoted on the second section on one side of thepivotal connection between the first and second section and having itsrear arm pivotally connected with the front arm of the first lever, anda link pivotally connected at its rear end with the front arm of saidsecond lever while its front end is connected with said third section onone side of the pivotal connection between said second and thirdsections.

3. An artificial limb comprising a palm, a digit pivoted on said palm,and means for shifting the digit relatively to said palm including adriven rotary member and a driving rotar member which engage each otherfrictional means for transmittingtmotion from said driven member to saiddlgit, and an operating device connected with said driving member.

4. An artificial limb, comprising a palm, a digit pivoted on said palm,and means for shifting the digit including a worm gear segment connectedwith said digit, a worm meshing with said segment and having a conicalfriction surface, a driving head having a conical friction surfaceengaging with the corresponding surface of the worm, and a spring whichpresses said worm and head together.

5. An artificial limb, comprising a palm, a digit pivoted on said palm,and means for shifting the digit including a worm gear segmentconnected; with said digit, a worm meshing with said segment and havinga conical friction surface, a driving head having a conical frictionsurface engaging with the corresponding surface of the worm, a

spring which presses said worm and head together, and means for turningsaid head including a sprocket whecl connected with said head, and achain belt passing around said sprocket wheel.

6. An artificial limb comprising a palm, a di '1; pivoted on said almand means for shifting the digit relatively to said palm including adriven rotary member and a driving rotary member which engage each otherfrictionally, means for transmitting motion from said driven member tosaid digit, an operating device connected with said driving member, andmeans for locking the digit against inward or folding motion.

7. An artificial limb, comprising a palm, a plurality of digits pivotedto said palm, a

multiple operating mechanism for actuating the several digits includinga worm gear segment connected with each digit, a worm mesh ing with eachworm segment and provided with a conical friction face, a drivlng headhaving a conical friction face engaging with the friction face of eachof said worms, a spring for pressing each of said heads against thecorresponding worm, a driven sprocket wheel turning with each of saidheads, a master driving sprocket wheel, idle sprocket wheels arrangedbetween adjacent driven sprocket wheels, and a chain belt passing aroundsaid master, driven and idle sprocket wheels.

8. An artificial limb comprising a palm, a plurality of digits pivotedto said palm, a multiple operating mechanism for actuating the severaldigits including a worm gear segment connected with each digit, a wormmeshing with each worm segment connected with each digit, a worm meshingwith each worm segment and provided with a conical I friction face, adriving head having a con;- ical friction face engaging with thefriction face of each of said worms, a spring for pressin each of saidheads against the correspon in worm, a driven sprocket wheel turningwith each of said heads, a master driving sprocket wheel, two shiftinglines connected with said master wheel on opposite sides of its axis,and a chain belt passin around said master and the several drivensprocket wheels.

9. A11 artificial limb, comprising a palm, digits, pivoted on said palm,a wrist on which said alm is ivoted to turn laterally,

and means or simu digits and palm.

10. An artificial limb, comprising a palm, digits pivoted on said palm,awrist on which said palm is pivoted to turn laterall and means forsimultaneously operating said digits and palm including means whichperrmt independent movement of said digits and palm.

taneously operating sald erally relatively to the latter, and means foroperating said palm including a worm gear segment connected with saidpalm, a worm meshing with said se ent, means for turning said worm incluing a driven sprocket wheel connected with said worm and a chain beltpassing around said sprocket wheel, and yielding means for holding saidworm against axial movement.

13. An artificial limb, comprising awrist, a palm pivoted on said wristto turn laterally relatively to the latter, and means for operating saidpalm including a worm gear segment connected with said palm, a wormmeshin with said se ment, means for turning sai worm inclu ing a drivensprocket wheel connected with said worm and a chain belt passing aroundsaid sprocket wheel, a shaft upon which said worm and sprocket wheel aremounted, and springs arranged on said shaft and bearing midst of) ositeends of said worm and sproc et whee 14. An artificial limb, comprising aforearm, a wrist pivoted on said forearm to turn wheel and means foractuating said worm.

15. An artificial limb comprising a forearm, a wrist pivoted to turn onsaid forearm about a longitudinal axis, an arm to which said forearm ispivoted to turn laterally, and means for turning said wrist including aworm wheel connected with said wrist, and a worm meshing with said wormwheel and operatively associated with said arm to receive motiontherefrom.

16. An artificial limb, comprising a forearm, a wrist pivoted on saidforearm to turn about a longitudinal axis, an arm to which said forearmis pivoted to permit the latter to turn laterally, and means for turningsaid wrist by motion from said arm, including a worm wheel connectedwith said wrist, a worm mounted on said forearm and meshing with saidworm wheel, a gear pinion connected with said worm, and a gear rackmeshing with said pinion and. pivotally connected with said a Intestimony whereof we aifix our signatures.

ALBERTO PEGORELLA. VINCENT PATRICOLO. FREDERICK H. APEL.

